Safety tipping mechanism for tipping trays on a continuous conveyor

ABSTRACT

A safety tipping mechanism for use in tray conveyor systems for mail parcels and the like contains a rotatable feature so that a loaded tray reaching two tipping mechanisms simultaneously causes the tipping mechanisms to rotate away from the tray without tipping the tray and damaging both tipping mechanisms. The tray then continues along the conveyor to a standby tipping station where it is safely tipped and unloaded.

United States Patent 11 1 Scata SAFETY TIPPING MECHANISM FOR TIPPING TRAYS ON A CONTINUOUS CONVEYOR [75] Inventor: Mario Scata, Monzo, Italy {73] Assignee: International Standard Electric Corporation, New York, N.Y.

221 Filed: Nov. 8, 1973 21 Appl. No.: 414,056

[30] Foreign Application Priority Data Nov. 22, 1972 Italy 31937/72 [52] US. Cl 198/38,198/155, 214/11 R [51] Int. Cl. 865g 47/46 [58] Field of Search 198/38, 146, 155;

214/11 R; 105/241 C, 261' R, 268, 270; 267/174y209/74 R [56] References Cited UNITED STATES PATENTS 3,034,665 5/1962 Speaker 214/11 1 51 Feb. 11, 1975 3,119,488 1/1964 Rabinow et a1. 198/38 3,167,192 l/l965 .Harrison et a1. 198/38 3,231,066 l/l966 Harrison et a1. 198/38 3,265,190 8/1966 Boehm 198/38 3,269,520 8/1966 Bishop et a1. 198/38 Primary Examiner- Von C. Blunk Assistant ExaminerRichard K. Thomson Attorney, Agent, or FirmJohr1 T. O'Halloran;

Menotti Lombardi, Jr.; Richard Menelly [57] ABSTRACT A safety tipping mechanism for use in tray conveyor systems for mail parcels and the like contains a rotatable feature so that a loaded tray reaching two tipping mechanisms simultaneously causes the tipping mechanisms to rotate away from the tray without tipping the tray and damaging both tipping mechanisms. The tray then continues along the conveyor to a standby tipping station where it is safely tipped and unloaded.

4 Claims, 3 Drawing Figures PATENTEB FEB] 1 I975 SHEET 1 BF 3 WENTEB 3.865.226

SHEET 30F 3 SAFETY TIPPING MECHANISM FOR TIPPING TRAYS ON A CONTINUOUS CONVEYOR BACKGROUND OF THE INVENTION The present invention relates to a safety tipping mechanism for tipping trays on a continuous conveyor for articles in general, more particularly for postal articles such as letters, post cards, covers, printed matter, parcels and the like.

In modern machines for postal sending of correspondence, use is made of conveyors having continuously moving trays which are caused to tip at predetermined locations where the conveyed material is unloaded into a bag destined for a given destination. The trays are caused to be tipped by suitable tilting devices controlled by an electric control according to an addressing code.

The trays with the respective support and driving members move along the conveyor line at a high speed. Because the mass of such tilting devices is large, a sudden stopping due to an unforseen malfunctioning of a SUMMARY OF TI-IE INVENTION According to the present invention there is provided a tipping device capable of resiliently rotating upon contact with another tray, thereby allowing the tray to move forward should the tray not be tipped at a predetermined station.

By making use of such safety devices each tray that is prevented from tipping due to the fact, for example, that two tilting devices are in the same working position on either side of the conveyor at the same time does not meet any real obstacle along its course, since the two non-rigid tilting devices resiliently yield to allow the tray to advance without being tipped; the tray then is able to discharge its contents onto an auxiliary waste unloading station. During normal operation the tilting devices only slightly rotate sufficient to lessen the impact against the tilting device of the moving tray, while the rotation of the tilting devices is a maximum when the tray fails to tip.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a side view of the electromagnetic safety tipping device used for tilting or tipping trays on a continuous conveyor;

FIG. 2 shows a perspective view of a tray in its raised position; and

FIG. 3 is a front cross section view of the tray shown in FIG. 2 arranged in its horizontal position.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1, a ball bearing 1 is secured to a moving lever or arm 2. The lever 2 is rotatably mounted on pins 3 (only one being visible in the figure) aligned along the axis of rotation of the moving-lever 2.

The latter is lifted due to the action of the core 8 in the electromagnet 9 when energized, thus being caused to move in the direction of arrow A from the rest position shown to the position 20 indicated with dashed lines. The connection between the core 8 and the moving lever 2 is made through an articulation pivoted at the ends thereof in two lugs of the lever itself and is connected at the intermediate portion thereof to one end of the core 8 of the electromagnet 9. Both the core 8 and the body of the electromagnet 9 are secured by means of pins 12 to a support, which in turn is fixed to the portion4. Such a pivotal connection allows the axis of the electromagnet to be fit through an articulation at the position of the moving lever 2. A spring 19 which is connected at one end thereof to the lever 2 and at the other end to the support 4 supporting the whole mechanism, keeps the moving lever 2 in a rest position as illustrated by full lines.

The mechanism of this electromagnetic device mounted on the support 4 is yieldable as a whole. The

same may rotate against a tension spring 16 around a pin 6 extending from the base plate 5 and rotatably mounting the support 4 by passing through a bore 21 formed in the support itself.

The support 4 is in a rest position when resting with a side thereof on a locking screw 14 mounted on a support 13 secured to the base plate 5. The tension spring 16 is secured at one end to the support 4 and at the other end thereof to an outer support 15 also mounted on the base plate 5. The spring 16 is adjustably secured to a threaded pin 17 by a locking device 18. One function of the tension spring 16 is that of deadening during the normal operation the impact of the ball bearing 1 against the shaped profile or cam of a tray (FIGS. 2 and 3), thereby permitting a slight rotation of the support 4 With reference to FIGS. 2 and 3, the tray 22 is shown which may betipped from either side through an angle of about 40 by rotating on two support shafts 26 secured to a plate 28 which is actuated by driving devices 27 (such as chains, ropes or belts) in the direction indicated by the arrow B.

The tray 22 has front and rear edges 23 and 25 bent according to a circumscribed circumference, the front edges being longer than the rear edges, while the central portion is so shaped as to define two inclined planes 24, one on the right side and the other on the left side (not visible on FIG. 2) thereby acting as cams. The tray 22 is usually arranged in a horizontal position by means of conventional spring devices also not shown on FIG. 2. While being moved forward by the devices 27 in the direction of the arrow B, the tray 22 contacts through one of its cams 24 one of the ball bearings 1 of the tilting device on the left or right side, depending upon which of the two mechanisms is brought into an operative or working position upon energization of the .respective electromagnet.

Along its path the tray 22 is caused to be tilted or turned over-rightwise or leftwise by being raised by the cam or inclined plane 24 on a corresponding ball bearing 1 in order to unload the material thereon in that position.

Should an error occur in controlling the two opposite tipping mechanisms shown in detail on FIG. 3 so that the respective electromagnet 9 now shown on FIG. 3 is energized while the moving lever 2 thereof is in a working position, then the forward moving tray 22 engages both its cams 24 with the ball bearings 1 of the moving levers 2 at the same time without overtaking the inclined planes. During this misfunction caused by two tipping devices acting at the same time on a single tray, the embodiment according to the present invention avoids the blocking of both the tray and the machine. These two left and right yielding tilting devices may rotate sufficiently on the respective pins 6 so as to cause the respective ball bearings l to move away from the cams 24 of the tray, allowing the tray to slide off the cams once the tipping devices have been returned to rest by the respective springs 16. The stopping of the machine is thus avoided along with the accompanying damage thereto, and the articles on the tray arrive at the waste container at the end of the conveyor without being erroneously unloaded.

One of the advantages of the tilting device according to the present invention is that should one become inoperative-it may readily be replaced with a new tilting device by simply removing it from the pin on which it is rotatably mounted. This feature provides fast maintenance with periods of time loss along with high operating efficiency of the machine since possible failure of the tilting device does not stop the operation of the machine although the overall efficiency of the same may be reduced to some extent.

It should be understood that the above description of one specific embodiment of the invention is not to be considered as a limitation to the scope thereof, along with any modifications which would become apparent to a person skilled in the art from the above description of the invention.

I claim:

1. The safety tipping mechanism for a continuous conveyor system of the type having moving tray assemblies comprising:

a base plate;

a support rotatably mounted on said base plate and attached to an upright extension thereon by means of a spring;

a moving lever pivotably mounted to said support;

bearing meansattached to the top surface of said moving lever;

a first articulation pivotably attached to a bottom surface-of said moving lever;

an electromagnet pivotably mounted to said support at one end, and having a slidable core coupled to i said first articulation at the other end, said electromagnet is energized to force said moving lever to move from a non-tipping position to a tipping position; and

means for permitting rotation of said tipping mechanism during malfunctioning in order to prevent jamming of said tipping mechanism whereby a predirected force applied to said bearing means causes said support to rotate against the tension of said spring and said support is returned to its rest position when said predirected force is removed.

2. The safety tipping mechanism of claim 1 wherein said moving tray assembly contains two said camming surfaces one on each side of said tray assembly wherein said moving tray slidably engages said bearing means during transport, so that when said tray is unable to tip a predetermined force is exerted upon saidbearing means causing said supports corresponding to said bearing means to rotate against said springs to cause bearing means to slidably disengage from said camming surfaces leaving said trays in an untipped position.

3. In a conveyor system having a tipping mechanism and moving trays with means forengaging the trays by the tipping mechanism, the improved tipping mechanism comprising:

a. a base member;

b. said tipping mechanism rotatably mounted at a point on said base member for engaging and tipping said tray and capable of rotating upon application of a predetermined force; and I c. a spring fixedly attached between said base member and said tipping mechanism to enable rotation of said tipping mechanism a predetermined distance about said point when one said tray is engaged by more than one tipping mechanism, whereby jamming of said tipping mechanism is thereby prevented in the process.

4. The improved tipping mechanism of claim 3 including stop means mounted on said base and positioned to prevent rotation of said tipping mechanism in a direction opposed to the movement of said trays. 

1. The safety tipping mechanism for a continuous conveyor system of the type having moving tray assemblies comprising: a base plate; a support rotatably mounted on said base plate and attached to an upright extension thereon by means of a spring; a moving lever pivotably mounted to said support; bearing means attached to the top surface of said moving lever; a first articulation pivotably attached to a bottom surface of said moving lever; an electromagnet pivotably mounted to said support at one end, and having a slidable core coupled to said first articulation at the other end, said electromagnet is energized to force said moving lever to move from a non-tipping position to a tipping position; and means for permitting rotation of said tipping mechanism during malfunctioning in order to prevent jamming of said tipping mechanism whereby a predirected force applied to said bearing means causes said support to rotate against the tension of said spring and said support is returned to its rest position when said predirected force is removed.
 2. The safety tipping mechanism of claim 1 wherein said moving tray assembly contains two said camming surfaces one on each side of said tray assembly wherein said moving tray slidably engages said bearing means during transport, so that when said tray is unable to tip a predetermined force is exerted upon said bearing means causing said supports corresponding to said bearing means to rotate against said springs to cause bearing means to slidably disengage from said camming surfaces leaving said trays in an untipped position.
 3. In a conveyor system having a tipping mechanism and moving trays with means for engaging the trays by the tipping mechanism, the improved tipping mechanism comprising: a. a base member; b. said tipping mechanism rotatably mounted at a point on said base member for engaging and tipping said tray and capable of rotating upon application of a predetermined force; and c. a spring fixedly attached between said base member and said tipping mechanism to enable rotation of said tipping mechanism a predetermined distance about said point when one said tray is engaged by more than one tipping mechanism, whereby jamming of said tipping mechanism is thereby prevented in the process.
 4. The improved tipping mechanism of claim 3 including stop means mounted on said base and positioned to prevent rotation of said tipping mechanism in a direction opposed to the movement of said trays. 